I am with kinnem....shocker I know!
Khakis and collared shirt. If he wants to wear a blazer he can just keep it in the car and run to get it, instead of changing his entire wardrobe.
Honestly the school tour is a dog and pony show. It is just a big old group walking around with nobody paying attention to anybody else. (I have 3 kids, so I have been there, done that AND paid the check).
Secondly, the CoC/PMS understand that you are combining the tour with the interview. I would not enter in shorts, but to me wearing a suit is just over the top.
~ Our DS did not even wear a suit for his MoC interviews. He wore blazer, dockers and collared shirt. MoC he did wear a tie.
~ I work for a national men's clothing company in VA. I have many parents that come in thinking they have to spend several hundreds of dollars to outfit them for this one day. As a parent of now an ADAF pilot, I tell them NO, unless they are going to combine this suit with something like homecoming or a family function they know is coming up in the future, such as a wedding or maybe their graduation. Instead, I sell them the following.
~~ Blue or black blazer. Khaki pants. NO WHITE SHIRTS, but instead something in a powder blue. NO RED ties, instead the college school color. Brown shoes.
~~~ Why? Because depending on how big that unit is they (PMS) will interview tons of kids. You want them to remember him/her right away and not be one of the cookie cutter candidates with what they are wearing, but at the same time be classic.
IMPO, what I would pay more attention to is the following:
1. Little things matter
~ Polish the shoes.
~ Cut the fingernails
~ Get a haircut. I am not saying a buzz cut, but a trim. DS has insanely curly hair. His hair was touching his collar, and over his ears, but it was trimmed to his style.
~ Take a resume
~ Be prepared to ask questions
~~ IE AFROTC is a 2+2 scholarship, ask % that get SFT. If they want rated ask % that get UPT.
~ Be prepared to have questions from the left field
~~ I see you have all A's in Math, but your SAT super is 610, why?
~ Let him enter on his own.
~~ Agree to meet him a designated area, such as the student union. This will allow him to get a feel for the campus next yr as a freshmen. See above about dog/pony. College kids know these are tours, they will steer clear. However, him walking back alone to meet you, he is just another college student.
Hope that helps
OBTW, DS got all 3 MoC noms, and an AFROTC scholarship, all with wearing just a blazer and khakis. It was his resume, and how he conducted himself in the interview that got it!
PS if your DS is not use to wearing a suit, make him wear it at home the night before. Nothing worse than watching somebody squirm during an interview because they don't know how to sit in a jacket. IE sits on the tail of the coat or forgets to unbutton the suit jacket when they sit down.